rs1556464116

Variant names:

• chrX-37780112-TTTTTGTCATTG-T
• rs1556464116
• NM_000397.4:c.37_45+2delTTTGTCATTGT

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PP5_Moderate

The NM_000397.4(CYBB):​c.37_45+2delTTTGTCATTGT​(p.Phe13_Ile15del) variant causes a splice donor, conservative inframe deletion, splice region, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. It is difficult to determine the true allele frequency of this variant because it is of type DEL_BIG, and the frequency of such variant types in population databases may be underestimated and unreliable. Variant has been reported in ClinVar as Pathogenic (★). Synonymous variant affecting the same amino acid position (i.e. F13F) has been classified as Likely benign.

• Frequency: Genomes: not found (cov: 22)
• Consequence: CYBB NM_000397.4 splice_donor, conservative_inframe_deletion, splice_region, intron
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.04
• Publications: 0 publications found

Genes affected

CYBB (HGNC:2578): (cytochrome b-245 beta chain) Cytochrome b (-245) is composed of cytochrome b alpha (CYBA) and beta (CYBB) chain. It has been proposed as a primary component of the microbicidal oxidase system of phagocytes. CYBB deficiency is one of five described biochemical defects associated with chronic granulomatous disease (CGD). In this disorder, there is decreased activity of phagocyte NADPH oxidase; neutrophils are able to phagocytize bacteria but cannot kill them in the phagocytic vacuoles. The cause of the killing defect is an inability to increase the cell's respiration and consequent failure to deliver activated oxygen into the phagocytic vacuole. [provided by RefSeq, Jul 2008]

CYBB Gene-Disease associations (from GenCC):

• granulomatous disease, chronic, X-linked

  Inheritance: XL Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• chronic granulomatous disease

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked Mendelian susceptibility to mycobacterial diseases due to CYBB deficiency

  Inheritance: XL, Unknown Classification: SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae)

ENSG00000250349 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PP5: Variant X-37780112-TTTTTGTCATTG-T is Pathogenic according to our data. Variant chrX-37780112-TTTTTGTCATTG-T is described in ClinVar as Pathogenic. ClinVar VariationId is 533560.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYBB	NM_000397.4	c.37_45+2delTTTGTCATTGT	p.Phe13_Ile15del	splice_donor_variant, conservative_inframe_deletion, splice_region_variant, intron_variant	Exon 1 of 13	ENST00000378588.5	NP_000388.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYBB	ENST00000378588.5	c.36_45+1delTTTTGTCATTG	p.Phe13GlyfsTer18	frameshift_variant, splice_donor_variant, splice_region_variant, intron_variant	Exon 1 of 13	1	NM_000397.4	ENSP00000367851.4
ENSG00000250349	ENST00000465127.1	c.171+354113_171+354123delTTTTGTCATTG		intron_variant	Intron 3 of 8	5		ENSP00000417050.1

Frequencies

GnomAD3 genomes Cov.: 22

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome Cov.: 22

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Granulomatous disease, chronic, X-linked Pathogenic:1

Jul 26, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Disruption of this splice site has been observed in individuals with chronic granulomatous disease (PMID: 31813112; Invitae). For these reasons, this variant has been classified as Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. ClinVar contains an entry for this variant (Variation ID: 533560). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a splice site in intron 1 of the CYBB gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in CYBB are known to be pathogenic (PMID: 9585602, 20729109). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		9.0
Mutation Taster		=0/200	disease causing (ClinVar)

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1556464116; hg19: chrX-37639365;